Production of blue dyestuffs of the halogenated anthracene series



25 advantageous.

Patented Sept. 29,1931

UNITED STATE S PATENT v OFFICE PAUL NAWIASKY. Ann ARTUR KRAUSE, orLUDWIGSHAFEN-ON-THE-RHINE,' GER- MANY, ASSIGNORS '20 GENERALANILINEwon-Ks INC., on new YORK, max, A con- PORATION OF DELAWAREPRODUCTION OF BLUE DYESTUFFS THE HAIJOGENATED ANTHRAGENE No Drawing.Application filed March 28, 1929, Serial No. 350,812, and in GermanyJuly 2 5, 1 928.

The present invention relates to the production of blue dyestuffs of theantliracene series which contain halogen. 7

We have found that valuable blue derivatives ofN-dihydro-1,2,2,1-anthraquinoneazine are very easily obtained by actingupon 1,2,2",1'-"anthraquinoneazine, suspended 1n sulphuric acidcontaining water, with a halo gen hydride. Generally speaking thesulphuric acid used should contain between about and 80 per cent ofwater. Sulphuric acid of to 7 5 per cent strength is particularlyInstead of the halogen hydrides, salts of the same which split offhalogen hydride by the action of the sulphuric acid used, may beemployed with advantage. The reaction proceeds so readily that theemployment of elevated pressure by working in closed vessels, which isadvantageous or even necessary in other methods of combining 1 ,2 ,2 ,1anthraquinoneazine with halogen hydrides, can be dispensed with. Theha-logenation products of the N-dihydroanthraquinoneazine are obtainedin a particularly pure state when pure azine, which is obtain able, forexample as described in our 'copending application for Patent Ser. No.350,811,-

' filed March 28, 1929, by treatment of commercialN-dihydroanthraquinoneazine in sulphuric acid solution with manganesedioxide, is employed as the initial material. In this case themanufacture of the pure 1,2,2,1-

anthraquinoneazine and the conversion of the same into halogenatedN-dihy'droe1,2,2',1'-

' anthraquinoneazine can be carried out in one operation. The reactionproceeds according to the following equation:

The followingexamples will further illustrate the nature ofthisinvention,-but the invention is not restricted thereto. The parts arebyweight. f

g g I 7 Example 1 V 5 parts of 1,2,2,l'-anthraquinoneazine obtainableaccording to Berichte der Deutschen Chemischen Gresellschaft volume 36,,page 3434, are suspended in 100 parts-of. I per cent sulphuric'acid. 35parts ofa saturate ed solutionof common salt are then allowed to dropslowl into the suspension at from to C. he whole is stirred for 2 hoursat from 95 to 100 C., and finally a pure blue suspension is obtained;The whole is diluted with water,'fil tered,washed with water and thedyestufi is then worked up in the usual manner; I Emamplei? az'ineof asimilar degree of purity are dis solved in 1000 parts of sulphuric acidof 66 Baum. 50 parts of water are then-slowly poured in and then at from50 to 60 C. a Q

suspension of 40 parts of native pyrolusite in 200 parts of sulphuricacid of 66 Baum are added. The whole is stirred for 5 hours at about(3., cooled to about 30 C. and then 800 parts of oleum containing 23 percent of SO are added, whereby part of the separated azine passesinto'solution. Then while stirring vigorously at a temperature below 30C. 800 parts of a concentrated solution of common salt are allowed torun in slowly. The whole is then heated to about 95 C. and another 600parts of common salt solution are allowed to run in slowly at a;

temperature above 95 C. The whole is then kept for about 2 hours at from95 to 100 C. until no further change in the blue dioxide and treatingtheresulting product,

suspended in sulphuric acid of from 50 to 80 per cent strength, with ahalogen hydride.

In testimony whereof we have hereunto set our hands.

PAUL NAWIASKY. ARTUR KRAUSE.

color ofthe suspension can be detected. The 7 whole is then diluted withwater and the dyestufl' is workedup as described in Ex-' ample 1. Thedyestufi" is a chlorinated N- dihydroanthraquinoneazine which dyescotton particularly pure shades having oomparatively very good fastnesstochlorine'.

Ewample 3 p 30 parts of pure N-dihydro-1,2,2,1-anthraquinoneazine, suchas is obtainable for example according to the U. S; Patent No.1,541,156, are dissolved in 600 parts of sulphu'ricacid of 66 B.strength,whereupon 12 parts of natural manganese dioxide are introducedat between 25 and 30 centigrade. After an hour, the mass is diluted with300' parts of ice and 500-partslof con 3 centrated hydrochloric acid areadded; The

mixture is boiled under a reflux condenser, while stirring, until a pureblue paste is formed, which takes about an hour, diluted with water andworked up as described in Example 1.

Example 4 V 10 parts of the N-dihydro-1,2,2',l anthraquinoneazine usedin Example 2 are dissolved in 100 parts of sulphuric acid of 66 B. 5partsof water are slowly added and then a suspension of 6 parts ofnatural manganese dioxide in 30 parts of 90 per cent sulphuric acid,whereupon the mass is heated for about 6 hours to between 65 and 70Centigrade. The mixture is cooled to about 30 centigrade, and 80 partsof fuming sulphuricacid containing 23 per cent of S0 are added in orderto dissolve the partly separated 'azine.

. Thereuponthe solution is diluted with parts of water and heated tobetween 90 V and 100 centigrade: 'At "a temperature above 95 centigrade,parts of a 10 per cent aqueous solution of sodium bromide are run in,and the mass is stirred for about 2 3 hours at between 95 and100centigrade. 7

until the reaction is complete. The resulting product is diluted withwater and worked up as described in Example 1. The

dyestuii contains bromine and has tinctorial

